Re: [dpdk-stable] [PATCH] vhost: fix async packed ring batch datapath

["Xia, Chenbo" <chenbo.xia@intel.com>]

> -----Original Message-----
> From: Jiang, Cheng1 <cheng1.jiang@intel.com>
> Sent: Thursday, July 8, 2021 6:25 PM
> To: maxime.coquelin@redhat.com; Xia, Chenbo <chenbo.xia@intel.com>
> Cc: dev@dpdk.org; Hu, Jiayu <jiayu.hu@intel.com>; Yang, YvonneX
> <yvonnex.yang@intel.com>; Jiang, Cheng1 <cheng1.jiang@intel.com>;
> stable@dpdk.org
> Subject: [PATCH] vhost: fix async packed ring batch datapath
> 
> We assume that in the sync path, if there is no buffer wrap in the
> avail descriptors fetched in a batch, there is no buffer wrap in the
> used descriptors which need to be written back in this batch, but
> this assumption is wrong in the async path since there are inflight
> descriptors which are processed by the DMA device.
> 
> This patch refactors the batch copy code and adds used ring buffer
> wrap check as a batch copy condition to fix this issue.
> 
> Fixes: 873e8dad6f49 ("vhost: support packed ring in async datapath")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Cheng Jiang <cheng1.jiang@intel.com>
> ---
> --
> 2.29.2

Applied to next-virtio/main, thanks.